A valve drive with a rocker arm of the type mentioned at the outset is known from the publication DE 42 34 868 A1. Here, the hydraulic valve clearance compensation element (hydraulic element) acting as a support element is installed in the cylinder head of the internal combustion engine and connected to its lubrication and hydraulic system. During operation of the internal combustion engine oil is ejected for lubrication and cooling via an oil ejection hole formed as a bore in the ball scraper of the rocker arm. Here, supported rotational at a rocker arm, a roller is lubricated and cooled, at which the cam rolls and here causes the deflection of the rocker arm.
Air is also inserted thereto, together with the oil to supply the hydraulic element, which can evacuate via the oil ejection hole. When in a valve drive an oil ejection hole is omitted in order to save and/or reduce the oil pumping performance and the lubrication and the cooling of the roller occurs in a different manner, depending on the design of the oil supply, a problem with noise may develop under certain operating conditions, e.g., in frequent motor starts or driving operation with very low average speeds. During start-up of the motor, the amount of air pumped together with the oil into the oil circuit and thus into the oil reservoir of the hydraulic valve clearance compensation element cannot evacuate quickly enough. Here, it is suctioned via the open return valve of the compensation element into its high-pressure chamber. This way, the compensation element becomes compressible, which leads to an elevated loss in stroke of the charge-cycle valve.
The closing speed of the valve increased here causes a noise, the so-called valve ticking. The leaking gap in the valve clearance compensation element between the top of the piston and the housing and/or the contact between the spherical end section of the support element and the ball scraper of the rocker arm prevent sufficient evacuation of air from the valve drive.